• Title/Summary/Keyword: Fuzzy-Set

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Evaluation of the parameters affecting the Schmidt rebound hammer reading using ANFIS method

  • Toghroli, Ali;Darvishmoghaddam, Ehsan;Zandi, Yousef;Parvan, Mahdi;Safa, Maryam;Abdullahi, Muazu Mohammed;Heydari, Abbas;Wakil, Karzan;Gebreel, Saad A.M.;Khorami, Majid
    • Computers and Concrete
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    • v.21 no.5
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    • pp.525-530
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    • 2018
  • As a nondestructive testing method, the Schmidt rebound hammer is widely used for structural health monitoring. During application, a Schmidt hammer hits the surface of a concrete mass. According to the principle of rebound, concrete strength depends on the hardness of the concrete energy surface. Study aims to identify the main variables affecting the results of Schmidt rebound hammer reading and consequently the results of structural health monitoring of concrete structures using adaptive neuro-fuzzy inference system (ANFIS). The ANFIS process for variable selection was applied for this purpose. This procedure comprises some methods that determine a subsection of the entire set of detailed factors, which present analytical capability. ANFIS was applied to complete a flexible search. Afterward, this method was applied to conclude how the five main factors (namely, age, silica fume, fine aggregate, coarse aggregate, and water) used in designing concrete mixture influence the Schmidt rebound hammer reading and consequently the structural health monitoring accuracy. Results show that water is considered the most significant parameter of the Schmidt rebound hammer reading. The details of this study are discussed thoroughly.

An Adaptive Tutoring System based on CAT using Item Response Theory and Dynamic Contents Providing (문항반응 이론에 의한 컴퓨터 적응적 평가와 동적 학습내용 구성에 기반한 적응형 고수 시스템)

  • Choi Sook-Young;Yang Hyung-Jeong;Baek Hyon-Ki
    • Journal of KIISE:Software and Applications
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    • v.32 no.5
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    • pp.438-448
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    • 2005
  • This paper proposes an adaptive tutoring system that provides learning materials dynamically according to the learners' teaming character and ability. Our system, in which a learning phase and a test phase are linked together, supports the personalized instruction-learning by providing the teaming materials by level in the learning phase according to the teaming ability estimated in the test phase. We design and implement a tutoring system consisted of an evaluation component and a learning component. An evaluation component uses a computerized adaptive test(CAT) based on item response theory to evaluate learners' ability while a learning component employs fuzzy level set theory so that teaming contents are provided to learners according to learners' level.

Automatic Recognition of the Front/Back Sides and Stalk States for Mushrooms(Lentinus Edodes L.) (버섯 전후면과 꼭지부 상태의 자동 인식)

  • Hwang, H.;Lee, C.H.
    • Journal of Biosystems Engineering
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    • v.19 no.2
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    • pp.124-137
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    • 1994
  • Visual features of a mushroom(Lentinus Edodes, L.) are critical in grading and sorting as most agricultural products are. Because of its complex and various visual features, grading and sorting of mushrooms have been done manually by the human expert. To realize the automatic handling and grading of mushrooms in real time, the computer vision system should be utilized and the efficient and robust processing of the camera captured visual information be provided. Since visual features of a mushroom are distributed over the front and back sides, recognizing sides and states of the stalk including the stalk orientation from the captured image is a prime process in the automatic task processing. In this paper, the efficient and robust recognition process identifying the front and back side and the state of the stalk was developed and its performance was compared with other recognition trials. First, recognition was tried based on the rule set up with some experimental heuristics using the quantitative features such as geometry and texture extracted from the segmented mushroom image. And the neural net based learning recognition was done without extracting quantitative features. For network inputs the segmented binary image obtained from the combined type automatic thresholding was tested first. And then the gray valued raw camera image was directly utilized. The state of the stalk seriously affects the measured size of the mushroom cap. When its effect is serious, the stalk should be excluded in mushroom cap sizing. In this paper, the stalk removal process followed by the boundary regeneration of the cap image was also presented. The neural net based gray valued raw image processing showed the successful results for our recognition task. The developed technology through this research may open the new way of the quality inspection and sorting especially for the agricultural products whose visual features are fuzzy and not uniquely defined.

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An Efficient Artificial Intelligence Hybrid Approach for Energy Management in Intelligent Buildings

  • Wahid, Fazli;Ismail, Lokman Hakim;Ghazali, Rozaida;Aamir, Muhammad
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.13 no.12
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    • pp.5904-5927
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    • 2019
  • Many artificial intelligence (AI) techniques have been embedded into various engineering technologies to assist them in achieving different goals. The integration of modern technologies with energy consumption management system and occupant's comfort inside buildings results in the introduction of intelligent building concept. The major aim of this integration is to manage the energy consumption effectively and keeping the occupant satisfied with the internal environment of the building. The last few couple of years have seen many applications of AI techniques for optimizing the energy consumption with maximizing the user comfort in smart buildings but still there is much room for improvement in this area. In this paper, a hybrid of two AI algorithms called firefly algorithm (FA) and genetic algorithm (GA) has been used for user comfort maximization with minimum energy consumption inside smart building. A complete user friendly system with data from various sensors, user, processes, power control system and different actuators is developed in this work for reducing power consumption and increase the user comfort. The inputs of optimization algorithms are illumination, temperature and air quality sensors' data and the user set parameters whereas the outputs of the optimization algorithms are optimized parameters. These optimized parameters are the inputs of different fuzzy controllers which change the status of different actuators according to user satisfaction.

Vibration Control Performance Evaluation of Hybrid Mid-Story Isolation System for a Tall Building (하이브리드 중간층 지진격리시스템의 고층 건물 진동 제어 성능 평가)

  • Kim, Hyun-Su;Kang, Joo-Won
    • Journal of Korean Association for Spatial Structures
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    • v.18 no.3
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    • pp.37-44
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    • 2018
  • A base isolation system is widely used to reduce seismic responses of low-rise buildings. This system cannot be effectively applied to high-rise buildings because the initial stiffness of the high-rise building with the base isolation system maintains almost the same as the building without the base isolation system to set the yield shear force of the base isolation system larger than the design wind load. To solve this problem, the mid-story isolation system was proposed and applied to many buildings. The mid-story isolation system has two major objectives; first to reduce peak story drift and second to reduce peak drift of the isolation story. Usually, these two objectives are in conflict. In this study, a hybrid mid-story isolation system for a tall building is proposed. A MR (magnetorheological) damper was used to develop the hybrid mid-story isolation system. An existing building with mid-story isolation system, that is "Shiodome Sumitomo Building" a high rise building having a large atrium in the lower levels, was used for control performance evaluation of the hybrid mid-story isolation system. Fuzzy logic controller and genetic algorithm were used to develop the control algorithm for the hybrid mid-story isolation system. It can be seen from analytical results that the hybrid mid-story isolation system can provide better control performance than the ordinary mid-story isolation system and the design process developed in this study is useful for preliminary design of the hybrid mid-story isolation system for a tall building.

Dynamic Hand Gesture Recognition Using CNN Model and FMM Neural Networks (CNN 모델과 FMM 신경망을 이용한 동적 수신호 인식 기법)

  • Kim, Ho-Joon
    • Journal of Intelligence and Information Systems
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    • v.16 no.2
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    • pp.95-108
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    • 2010
  • In this paper, we present a hybrid neural network model for dynamic hand gesture recognition. The model consists of two modules, feature extraction module and pattern classification module. We first propose a modified CNN(convolutional Neural Network) a pattern recognition model for the feature extraction module. Then we introduce a weighted fuzzy min-max(WFMM) neural network for the pattern classification module. The data representation proposed in this research is a spatiotemporal template which is based on the motion information of the target object. To minimize the influence caused by the spatial and temporal variation of the feature points, we extend the receptive field of the CNN model to a three-dimensional structure. We discuss the learning capability of the WFMM neural networks in which the weight concept is added to represent the frequency factor in training pattern set. The model can overcome the performance degradation which may be caused by the hyperbox contraction process of conventional FMM neural networks. From the experimental results of human action recognition and dynamic hand gesture recognition for remote-control electric home appliances, the validity of the proposed models is discussed.

Design and Implementation of Web Directory Engine Using Dynamic Category Hierarchy (동적분류에 의한 주제별 웹 검색엔진의 설계 및 구현)

  • Choi Bum-Ghi;Park Sun;Park Tae-Su;Song Jae-Won;Lee Ju-Hong
    • Journal of Internet Computing and Services
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    • v.7 no.2
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    • pp.71-80
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    • 2006
  • In web search engines, there are two main methods: directory searching and keyword searching. Keyword searching shows high recall rate but tends to come up with too many search results to find which users want to see the pages. Directory searching has also a difficulty to find the pages that users want in case of selecting improper category without knowing the exact category, that is, it shows high precision rates but low recall rates. We designed and implemented a new web search engine to resolve the problems of directory search method. It regards a category as a fuzzy set which contains keywords and calculate the degree of inclusion between categories. The merit of this method is to enhance the recall rate of directory searching by expanding subcategories on the basis of similarity.

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Characteristics and Application of Large-area Multi-temporal Remote Sensing Data (광역 시계열 원격탐사자료 분석의 특성과 응용)

  • 성정창
    • Korean Journal of Remote Sensing
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    • v.16 no.1
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    • pp.1-11
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    • 2000
  • Multi-temporal data have been used frequently for analyzing dynamic characteristics of ecological environment. Little research, however, shows the characteristics and problems of the analysis of continental- or global-scale, multi-temporal satellite data. This research investigated the characteristics of large-area, multi-temporal data analysis and the problems of phenological difference of ground vegetation and scarcity of training data for a long term period. This research suggested a latitudinal image segmentation method and an invariant pixel method. As an application, the image segmentation and invariant pixel methods were applied to a set of AVHRR data covering most part of Asia from 1982 to 1993. Fuzzy classification results showed the decrease of forests and the increase of croplands at densely populated areas, however an opposite trend was detected at sparsely populated or depopulated areas.

Study on Influencing Factors of Port Logistics Development Based on Configuration Analysis QCA

  • Li, Jian;Lee, Sang-Chun;Hong, Seung-Lin
    • Journal of Korea Trade
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    • v.25 no.5
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    • pp.58-73
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    • 2021
  • Purpose - In the context of economic globalization and the continuous development of international trade, as countries around the sea peninsula, port construction is particularly important. Based on the research on the influencing factors of port logistics development based on the allocation analysis, QCA (Qualitative Comparative Analysis) provides the basis for the planning and policy of port logistics development and has important theoretical value and practical significance for improving the level of port logistics management, reducing logistics operating costs and increasing economic benefits. In the tide of global integration for the development of port logistics, promote the growth of foreign trade economy of the city. It is also of great significance to the development and progress of commerce and trade. Design/methodology - Based on the relevant data samples of various ports in South Korea, this paper uses fsQCA (fuzzy set Qualitative Comparative Analysis) to integrate and analyze the influence mechanism of port logistics development and extracts five influencing factors of port logistics development, including the port's scale and infrastructure in the hard environment, port-neighboring enterprises in the soft environment, hinterland economy and government support. Findings - The five factors are unable to separately constitute the necessary and sufficient conditions of port logistics development, only a combined model can influence lake port logistics development. The scale and infrastructure of the port itself and port-neighboring ring enterprises are the main core conditions, which work together on the port, affect the throughput capacity of the port, and promote the development of port logistics. When the port-neighboring enterprises are not complete and the scale is low, the growth of port throughput will be restrained and the development of port logistics will be affected, whether the hinterland economic benefits are general, the development of port-neighboring enterprises is insufficient, or the government supports are limited. Originality/value - Through the research on the development of port logistics in South Korea from the perspective of configuration, this paper finds the configuration influence of hard environment and soft environment on the development of port logistics, which has important theoretical and practical significance for better promoting the development of port logistics in South Korea.

Married Women's Economic Dependency and the Welfare State (기혼여성의 경제적 의존과 복지국가)

  • Kim, Young-mi
    • Korean Journal of Social Welfare Studies
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    • no.36
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    • pp.55-80
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    • 2008
  • Research on the welfare state or income inequality has been concerned with variations in inequality between societies or families. These studies tend to view the family as a unit of shared interests where incomes are pooled and distributed equally. This study makes a theoretical and empirical case for why it is important to look at economic dependency within the family in comparative welfare state research. Using the Luxembourg Income Study data this study examined married women's dependency on their husbands' earnings in 16 western industrialized countries. The constructed measure for married women's level of economic dependency followed the procedure of Sørensen & McLanahan(1987), which stated : "her dependency is measured by the extent to which a woman's standard of living(as determined by her share of income) is derived from a transfer from her husband." The finding suggested that married women's economic dependence was lowest in Scandinavian countries. On the contrary, in Southern Europe countries most married women were dependent on husbands' earnings. In Netherlands, Austria, Germany where the share of part-time work among married women was high, married women's economic dependence was also high. This showed the women's labor force participation did not mean that the majority of couples were equal with respect to earnings, nor that a major shift in the sexual division of labour has taken place. This paper analysed the causal relationship between the married women's economic independence and the welfare state by using Ragin(2000)'s Fuzzy-Set Qualitative Comparative Analysis. This analysis considered the various conditions of the welfare state : namely, left power, union mobilization density, women's mobilization, public service sector employment and generous support on the family. The result showed that powerful union, high level of women's mobilization and the generous support on the family were necessary conditions for 'relatively high' level of married women's economic independence.